Ethanol fuel explained

By Cameron Kirby, 21 Oct 2016Car Advice

We look at some of the facts surrounding the cheaper fuel option at the bowser.

If you drive a petrol car you are traditionally faced with four options when you pull up to the bowser to refill your tank. You can top up using Premium 98 Octane, 95 Octane, standard 91 Octane, or the cheapest option, E10. But what is E10, what are its benefits, and what are the downsides?

E10 is a petrol mixture which contains 10-percent ethanol. Ethanol is a fuel which is based from food waste. Traditionally, Ethanol burns cleaner and cooler, providing performance that is more powerful and eco-friendly. However, it is less efficient, meaning it will return worse fuel mileage. Blending petrol with Ethanol in E10 is designed to provide the best of both worlds.

Most cars built after 1986 can safely run E10 fuel, with the exceptions being those with carburettors instead of direct injection, and high-powered vehicles. Always check your user manual to see what fuel can be used in your car. While E10 is a cheaper option than 91 Octane Fuel, it typically has an octane rating of 94.5, putting it in line with the middle of the range 95-Octane option.

Because E10 contains less energy than petrol, it burns quicker. Testing has shown that Premium 98 Octane fuel can be more efficient in both city and highway driving conditions than E10. However, depending on the price at the bowser, it could still be cheaper to fill up on the Ethanol blend, despite the poorer fuel mileage. It should be noted that premium fuel will always give you the best performance, and often has cleaning additive to help clean your engine.

While Ethanol is tougher on engines, according to the Royal Automobile Association of South Australia, several studies have shown using E10 fuel does not increase corrosion in normal, everyday operation.

It is important to differentiate E10 from E85, which is a heavier Ethanol blend. A car that is capable of running E10 usually cannot be filled up using E85.

At the end of the day, E10 provides a cheaper alternative to traditional fuels. Depending on prices it can be a money saving option. However, it is important to check if your car can use E10, and if the lack in efficiency doesn’t end up costing you more.